1. Technical Field of the Invention
The present invention relates to integrated circuits and more particularly to the production of bipolar transistors and insulated-gate field-effect transistors (MOSFET) in a semiconductor bulk (substrate). The invention finds an advantageous application in bipolar and BiCMOS technologies used in radio frequency applications.
2. Description of Related Art
A number of needs exist in the art with respect to the fabrication of bipolar transistors and insulated-gate field-effect transistors (MOSFET) in a semiconductor bulk (substrate). For example, it would be advantageous if the production of MOS transistors and bipolar transistors could be accomplished without any interference between the two processes used. Additionally, benefits would accrue if the bipolar transistor structure was compatible with the bipolar and BiCMOS technologies, and further if that structure was usable in radio frequency applications. A need also exists for reproducible structures possessing sub-micron emitters (for example, with a dimension of the order of 0.1 to 0.3 microns). It would also be advantageous if the bipolar transistor could be produced without emitter doping compensation. Lastly, a need exists for a process/structure which possesses minimized emitter-base distance such that base resistance and base/collector capacitance are reduced, thus allowing for an improvement in frequency performance.
The present invention address many, if not all, of the foregoing needs.